2sk77b and 2sk180 new projects

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I just want to buy this amp because of Tango OPT: rolleyes:
Is two cute mono block's but with that small psu transformer and only two filter caps, small heat sink´s
well it be better adapted to less powerful vfet's like 2SK82 and 5 watts of amplification power with such surrounding hardware.
Huge SIT Tokin 2SK180 have 300 watts of dissipation potential.
The sweet spot is find with much higher psu voltage ~ 60V, SIT bias is + 3A.
Naturally psu transformers need to be 600VA or more.... heavy giant heat sink´s
for 50 watts in Single-Ended pure class A without compromises.
Make more sense beefy transistor = lot's of power.
Vacuum tube DIY guys highly appreciate OTL ( output transformerless ) amplifiers because wide frequency bandwith response.
Less distortion without OPT that interesting too.
Easy to do with semiconductor's :)
On the photo speakers i can dream only from Tekne in Japan.
 

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Cascode and SIT

Could we build an amp with Tokin 2SK180 who use a cascode umbrella for lower distortion figures ?
IXYS hockey puck P-P follower at BAF2016 was an interesting example :umbrella:
 

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The one and only
Joined 2001
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A cascode which freezes the Vds across a SIT has the effect of making it
a little more like a Pentode. I'm not saying that's a bad thing, but it might
remove some of the charm that makes the SIT/VFET so interesting.

At the same time, the SIT has other properties, so a cascode would be
interesting to play with.

And possibly of greater interest, the cascode does not have to create
constant Vds on a SIT. You can use it to modulate Vds arbitrarily to
get whatever load line you like. A simple example of this is the F3,
where the Vds of the Jfet is modulated against output current to get
very low distortion.

(As an aside, the last Sony VFET amps had the VFETs cascoding bipolar
transistors...)
 

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Yes GnuB see the Japan link was show.
UFO SIT 1k Watt's space saucers are now on my work bench and waits for smart minimalistic style topology amplifier.
Congratulations to Diyers who find some as well :D
 

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